The present invention is directed to light fixtures and particularly to a florescent light fixture capable of replacing an incandescent light in a ceiling down-light.
Incandescent lamps have long been employed as down-lights in ceilings. In modern building construction, these lights are often mounting in fixtures above a suspended ceiling such that the depending bulb has a front glass near the plane of the suspended ceiling. These bulbs are normally screwed into the fixture by means of a standardized light socket for incandescent bulbs.
Incandescent bulbs have recently come into some disfavor because of the heat generated by the bulbs and because of the energy consumption and lack of lighting efficiency when compared with florescent lighting. National standards are ever increasing with respect to the amount of heat which can be conducted to a junction box, a ceiling and other near-by components. The incandescent light generates a significant amount of heat energy which can make such standards difficult to meet, particularly in ceiling mounted light fixture applications. On the other hand, florescent lighting generates far less heat which might be conveyed to such a junction box, ceiling or the like. However, florescent fixtures normally require substantially different mounting and socket systems than are required by incandescent bulbs; and replacement of incandescent lighting by florescent lighting has generally required major revisions to the building.
The level of efficiency of incandescent bulbs, as measured by the amount of light generated per unit of input power, is much lower than that for florescent lighting. Consequently, to obtain the same lighting effect, greater amounts of energy are required for any given situation. With the increase in the cost of power, incandescent lighting has become relatively costly. Again, switching to florescent lighting can also be very expensive because of the great differences in mounting and electrical hook-ups. The cost of switching to florescent lighting has often out-weighed any benefit achieved from the more efficient system.